Max, we design all of our own manufacturing test harnesses, and all of them use either an Arduino or a BeagleBone. It's quick, easy, cheap, and anyone can get the IDE, even if they're in a hotel in China. You can also get replacements in a single day.

This is becoming a more common occurrence. For example, I've used the Arduino Leonardo as a jumping off point in some of my designs. I picked it because the USB is built into the primary MCU, while the Uno and Mega require a separate MCU to handle the USB.

It reduces the complexity quite a bit, but the Leonardo MCU only comes in surface mount packages. That works for me, because I have Screaming Circuits (my day job) as a resource if I need SMT soldering. Although, I often hand solder my own small quantity surface mount boards because I enjoy it.

Mike - It's really a matter of trade offs. If you're only going to build a small quantity, have more time than money, and want to hand solder, you're probably better off going with thru-hole parts. If you plan on having it manufactured in more than just small quantities, surface mount is the way to go. The parts are less expensive, and it will cost less to get it manufacturered in high volume.

You can also look at something like the Arduino Micro (http://www.adafruit.com/products/1086) and plug it into the board with your custom hardware and connectors.

Again, it's kind of a trade off. Small quantities, it might be easier and less expensive to use something like the Micro. Larger quantities, it would be better to design a fully custom surface mount board.

@MikeCasale: I am working on a commercial application and using the Arduino to make a breadboard. To-date it is working great. I assumed I needed to design and manufacture my own Arduino-based PCB. I have worked as a Development Engineer for MANY years. I know designing a custom board can be VERY expensive.

If I don't do my own board, how do I make a reliable hardware product? I need to add a bunch of specialized electronics around the MPU. Do I design what they call "a shield"? Interconnections can be the downfall of a good design. Thanks for any help.

As you say, you can take the Arduino board open source files and use these as part of a larger custom board design -- making your own custom board isn't all that expensive -- you should talk to Duane about this.

The alternative is as you say to make your own shield that plugs on top of the Arduino -- you can get proto-shields from Adafruit.com for Unos (will also work with Leonardos) and Megas (will also work with Dues) -- but Duane and I opted to design our own (click here to see my blog on this).

Duane has also made a custom Arduino-based sensor board for his robot project -- he'll be blogging about that sometime in the next week or so.

Max engineers sometimes get carried away and want to do everything from scratch as it is what interests them.

To many engineers forget that they need to get the product to market quickly and cheaply as possible while ensuring it has maintained quality and performance. I have seen several systems and test systems which have utilised off the shelf demo boards and evaluation kits as part of the system to reduce the timescales, cost and project risk. This then allows more focus and time on the critical areas

I am working on a commercial application and using the Arduino to make a breadboard. To-date it is working great. I assumed I needed to design and manufacture my own Arduino-based PCB. I have worked as a Development Engineer for MANY years. I know designing a custom board can be VERY expensive.

If I don't do my own board, how do I make a reliable hardware product? I need to add a bunch of specialized electronics around the MPU. Do I design what they call "a shield"? Interconnections can be the downfall of a good design. Thanks for any help.